This invention concerns shredders for use, in shredding sheet materials such as paper. Such shredders are used, for example, in offices, banks, and other commercial and industrial establishments to shred confidental documents, to destroy used cheques, and for like purposes.
I have already proposed, in my prior British Pat. No. 1315320, a shredder construction which comprises a complementary pair of left-hand and right-hand square threaded screws arranged parallel to and in mesh with one another, and adopted for co-rotation in opposited directions, and means (which may be a handle or may be a motor) for rotating said screws.
With such a shredder, problems can arise in ensuring that the shreds, generated by operation of the shredder, do not accumulate in the grooves present between the lands of the threads of the screws. While we have already proposed a possible stripper arrangement, this has not proved to be particularly reliable in practice.